Fan



FebQll, 1947. ARN 2,415,621

FAN

Filed Oct 20. 1944 INVENTOR E6. 2.

ALBERT A. ARNHYM Y ATTORNE X Patented Feb. 11, 1947 FAN Albert A.Arnhym, Los Angeles, Calif., assignor to Solar Aircraft Company, SanDiego, Calif., a corporation of California Application October 20, 1944,Serial No. 559,588

3 Claims. 1

This invention relates to small electric fans used primarily forcirculating air to produce a cooling effect, although it may also beused to deliver heated air.

An object of the invention is to provide a gentle spreading stream ofclean air of relatively uniform velocity over its entire cross-sectionalarea.

Another object is to provide a fan in which the moving blades arecompletely surrounded and protected.

Another object is to provide an enclosed fan that is eiiicient and is ofsimple and inexpensive construction.

Other objects and features of the invention will appear from thedetailed description to follow of a specific embodiment thereof.

Briefly, the present invention consists of an electric fan ofconventional construction mounted within a cylindrical or drum-shapedcasing having an air filter in its rear end wall and an air distributorin its front wall, together with an inner shroud or transition forconverging the air from the fan into the deflecting structure forfacilitating the action of the latter in uniformly distributing the air.

In the drawing;

Fig. 1 is a rear view of a fan in accordance with the invention, withone half broken away to show the inner construction; and

Fig. 2 is a longitudinal vertical section taken in the plane II-II ofFig. 2.

The device comprises a cylindrical or drumshaped casing I having a baseI I secured to the under side for supporting it and having a handle I2secured to the top. The base II may be conveniently made insemi-cylindrical form with its flat face downward, this face beingprovided with feet I3 of rubber or the like so that the device can beset on a finished surface without marring it.

The base II may be secured to the casing III with bolts I4 and sheetmetal screws I5. The base may also have a hushed opening in its rear endWall I6 for the passage of a power cord l1, and a switch I8 ofconventional design may be mounted in the base with its handle extendingthrough an aperture to the exterior. The cord I1 extends to the switchI8 and thence through a hushed opening in the contacting portions of thebase II and casing I0 to the interior of the latter.

There is concentricall positioned within the casing I0 an electric motorI9 having a conventional fan secured to its shaft at the front end ofthe motor. The motor casing is supported by a spider, this spiderconsisting of a central band encircling the motor and four radiatingspoke elements 2| which extend almost to the casing wall II) where theyare joined to a cylindrical supporting band 22. The band 22 in turn issecured by brackets 23 and bolts 24to a transition member 25 which inturn is secured to the casing ID in a manner later to be described.

The motor-supporting spider is formed in four sections, each sectioncomprising a central quadrant adapted to lie against the cylindricalmotor I9 and straight end sections, each of which is joined to one ofthe straight end sections of the next adjoining quadrant. The two piecesforming each leg or spoke of the spider may be secured together by tabs26 out out of one piece and pressed through the other piece and bentback. To join the outer end of each. spoke to the cylindrical band 22,the spokes are provided with notches into which the band is pressed.

If it is desired that the device supply heated air, a pair of concentricheating coils 2i and 23 may be provided surrounding the motor I9. Eachcoil is in the form of an open helix and is sup-- ported by micainsulators 29 which are clamped between the two pieces forming each ofthe spoke members 2I. The heating coils are adapted to be selectivelyenergized by means of the switch I8 which is preferably a three-positionswitch having a neutral position in which the fan and coils arede-energized, a second position in which the fan is energized but thecoils are not, and a third position in which both the fan and the coilsare energized.

The transition member 25 is concentric with re spect to the outer casingIll but tapers from a large diameter at the rear end to a relativelysmall diameter in front of the fan. Thus the rear end of the transitionis of the same diameter as the casing It! and is secured directlythereto by the bolt I4 and additional circumferentially spaced bolts. Asbest shown in Fig. 2, the transition is only slightly larger in diameterthan the fan 20 in the plane of the fan and is of sornewhat smallerdiameter than the fan at its forward end where it merges into and isjoined to a mem ber 3I having a cylindrical portion 32 which extendsforwardly a short distance from the front wall of the transition. member25 and there merges into an outwardly flaring portion 33 which is curledback around the front edge of the casing Ill at its forward edge. Thereare positioned. within the flared section 33 two concentricallydisposed, generally conical baffles 34 and 35 which are supported fromthe member 33 by bolts 35 and spacer tubes 31 and 38.

The members 25 and 3! are preferably covered on the outside with acoating 45 of thermal and acoustic insulating material, such as felt todeaden the motor and fan sound.

Th rear end of the casing is closed by a filter element 39 whichcomprises inner and outer screen walls which contain therebetween asuitable oil impregnated porous material such as fiber glass capable ofabstracting most of the dust from the air without excessively impedingthe flow of air therethrough. A decorative retaining rim 40 may beprovided for holding the filter wall in' place, this rim being securedby screws 4| to brackets 42 which are welded or otherwise secured to theinner surface of the casing ID.

The structure described is capable of producing a very uniform anddiverging stream of air so that it is particularly adapted for use ondesks and the like in relatively close proximity to the person who is tobenefit from it. The air not only has a gentle uniform motion, but isrelatively clean because of the filtering effect of the porous rear wallof the casing. y

The baffles 34 and 35 in conjunction with the member 3| function torecirculate air in front of the housing and mix it with the airdelivered by the fan so that of the total air projected, about 70% comesthrough the fan and about 30% is recirculated. This makes it possible toheat the air passing through the housing to a higher temperature anddeliver more total heat without discomfort.

The device is relatively silent because of the enclosure of the fancompletely within the padded casing and because of the sound dampeningeffect of the rear filter wall.

The converging shroud or bafile 25 permits the use of a relatively largearea filter at the rear and to reduce the resistance to the infiow ofair while at the same time increasing the volumetric efficiency of thefan.

If desired, a reservoir 50 having a drip valve can be mounted in anaperture provided therefor in the housing, and connected by a tube 51 tothe filtering material 39 for supplying an oil base perfume or deodorantto the air.

Various departures from the exact construction shown can be made whilestill utilizing the essential novel features of the invention, and theinvention is to be limited only to the extent set forth in the appendedclaims.

I claim:

1. A device of the type described, comprising: a casing symmetricalabout a longitudinal axis and including a rear section of large diameterat its rear end which converges to a substantially smaller diameter atits forward end; a front section continuous at its rear end with thefront end of said rear section and flaring outwardly at its front end toa substantially larger diameter; auxiliary baffle means within saidflaring portion of said front section; and an electric fan mountedwithin said rear casing section for propelling air forwardlytherethrough, the rear end of said rear casing section and the front endof said front casing section being of the same diameter; and an outercylindrical housing joined to the outer ends of said front and rearcasing sections and forming an enclosure therefor.

2. A device of the type described. comprising: a casing symmetricalabout a longitudinal axis and including a rear section of large diameterat its rear end which converges to a substantially smaller diameter atits forward end; a front section continuous at its rear end with thefront end of said rear section and fiaring outwardly at its front end toa substantially larger diameter; auxiliary baffle means within saidfiaring portion of said front section; an electric fan within said rearcasing section for propelling air forwardly therethrough; means formounting said motor in said casing comprising a spider having an innerannular portion engaging the casing of said electric fan and having anouter ring and radial struts interconnecting said inner and outer rings;means for connecting said outer ring to said rear casing section; aheating coil concentrically disposed about the motor of said fan inlateral spaced relation to said fan and said casing; and insulatingsupports secured to said radial struts for supporting said heating coil.

3. A device of the type described, comprising: a casing symmetricalabout a longitudinal axis and including a rear section of large diameterat its rear end which converges to a substantially smaller diameter atits forward end; a front section continuous at its rear end with thfront end of said rear section and flaring outwardly at its front end toa substantially larger diameter; auxiliary baffle means within saidflaring portion of said front section; an electric fan mounted withinsaid rear casing section for propelling air forwardly therethrough;acoustically dampin filter means closing the rear end of said casing anda coating of acoustic insulating material on said front and rear casingsection, the rear end of said rear casing section and the front end ofsaid front casing section being of the same diameter; and an outercylindrical housing joined to the outer ends of said front and rearcasing sections and forming an enclosure therefor.

ALBERT A. ARNI-IYM.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,427,859 Schmidt Sept. 5, 19221,487,828 Ziganek et a1 Mar. 25, 1924 1,713,648 Feinberg et al May 21,1929 1,889,117 Adamcikas Nov. 29, 1932 1,906,408 Pearsons May 2, 19332,153,576 Kurth et al Apr. 11, 1939 2,258,731 Blumenthal Oct. 14, 19412,268,801 Carlton Jan. 6, 1942 2,298,576 McElroy et a1 Oct. 13, 19422,322,302 Martinson June 22, 1943 1,869,012 Kunian et al -July 26, 19322,149,689 Smith et a1 Mar. 7, 1939 1,942,758 Jessup Jan. 9, 19342,175,758 Neubert Oct. 10, 1939 1,993,158 Funk Mar. 5, 1935 2,130,910Smith, Jr Sept. 20, 1938 2,161,027 Dollinger June 6, 1939 2,225,398Hamblin Dec. 17, 1940

